1. Field of the Invention
The present invention relates to a press-connecting terminal which is electrically connected to a covered electric wire by pressing the covered electric wire into a gap between press-connecting blades formed on a pair of sidewalls.
2. Description of the Related Art
FIG. 4 shows a conventional press-connecting terminal 1. The press-connecting terminal 1 incorporates a contact portion 2 which is formed on one side of the terminal and to be connected to a mating terminal, and an electric wire joint 3 which is formed on the other side thereof and to be connected to the end of an electric wire. The electric wire joint 3 is provided with an electric-wire holding portion 4 for holding the electric wire on the rear side of the electric wire joint 3. Further, a press-connecting portions 5 is formed between the electric-wire holding portion 4 and the contact portion 2.
The press-connecting portion 5 comprises a bottom wall 6, a pair of sidewalls 7, 7 which are respectively bent upward in the substantially perpendicular direction from both sides of the bottom wall 6, and at least a pair of press-connecting blades 8, 8 which are bent so that these blades stand up from the respective sidewalls 7, 7 above the bottom wall 6 and face each other with a predetermined gap held therebetween. The press-connecting terminal shown in FIG. 4 has three pairs of press-connecting blades 8, 8.
The end portion of a covered electric wire 9 is pressed into a gap between the pair of press-connecting blades 8, 8 so as to rupture a covering portion (see FIG. 5) 10 of the covered electric wire 9 by means of the press-connecting blades 8, 8. When a conductor portion (see FIG. 5) 11 is brought into contact with the press-connecting blades 8, 8 the covered electric wire 9 and the press-connecting terminal 1 are electrically connected to each other. Incidentally, the covered electric wire 9 is clamped by the electric-wire holding portion 4 and held in the press-connecting terminal 1.
With tendencies for the size of housings of, for example, connectors to be reduced and for the density of terminals to be increased, there has developed a demand for reducing the size of such a press-connecting terminal 1 in order to decrease a storage space in the housing.
Thereupon, an attempt may be made to narrow the width of the press-connecting portion 5 as shown in FIG. 5 by setting the inside width L1 between the pair of sidewalls 7, 7 where the press-connecting blades 8, 8 are formed to be smaller than the external diameter L2 of the covered electric wire 9 in the press-connecting portion 5 to which the end portion of the covered electric wire 9 is press-connected.
When a covered electric wire 9 having an external diameter L2 equal to or greater than the inside width L1 between the pair of sidewalls 7, 7 is pressed into the gap between the press-connecting blades 8, 8 as shown in FIG. 6, however, the pair of sidewalls 7, 7 tend to widen outward due to the restoring force of the covered electric wire 9 during and after the press-fitting operation.
When the pair of sidewalls 7, 7 widen outward, there is the possibility that the contact load between the press-connecting blades 8, 8 and the conductor portion 11 of the covered electric wire 9 lowers, thus making the normal contact therebetween unobtainable.